Microscope warm stage.



T. LIDBERG.

MtCROSCOPE WARM STAGE.

APPLICATION FILED Junin, 1914.

Patented June 29, 1915'.

influences.

UNITED [STATES PATENT oEEIcE.

- v'.LIODOLIE LIDBERG, OF CHICAGO, ILLINOIS, ASSIGNOR OF ONE-HALF TO JOHN W.

' MORSBACH,.OF CHICAGO, ILLINOIS.

MICROSCOPE WARM STAGE.

citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful `Improvements in Microscope Warm Stages, of which Athe following is' a specification. i

My invention relates' to warm stages for microscopes.` Oneof the objects of my invention is to provide a preferably separable warm stage structure for microscopes whereby specil mens to be examined under the microscope maybe maintained at a predetermined, substantially constant temperature during such examination, or as long thereafter as may be desired.

Another object of my invention is to pro` vide a structure of suchcharacter that relatively large changes of temperature in the surrounding air or varying drafts of air will not sensibly affect the temperature of the subject `being operated upon because of the ready automatic response of the heating appliance to'fsupply additional'heat to com-f pensate for the chilling effect that would otherwise be Another object of my invention is to generally improve structures of this character.

Other and further objects will become readily apparent to 4persons skilled in the art, from a consideration of the following description when taken in connection with .the drawing, which is a part hereof, where- 1n- Figure 1 is an elevation of an ordinary microscope showing my warm stage in position' thereon. Fig. -2 1s a plan vlew of the supporting housing with the warming plate removed. Fig. 3 is a transverse section taken on line 3-3 of Fig. 1.

In all the views the same reference characters are employed to indicate similar parts. lThe warming plate 5 may be of insulating material, 4such as the material commonly known as vulcabeston and supposed -to comprise asbestos fiber mixed with some vulcanizable material, or the like, vprovided with a central perforation and' having its ,outer edges bound by metal rim 6. The heating wires 7, arev preferably wound sp1- `rally, as shown in Fig. 3, and are embedded inthe body portion of the plate 5. The

Specification of Letters latent.

produced by such extraneous,I

Patented June 29. 1915.

Application filed I une 24, 1914. Serial No. 846,940.

wires terminate as at 8 and 9 in screws that take into the body portion `of the plate.

A bottom cup shaped housing 10 is provided with a laterally deflected peripheral wall 11 perforated at intervals, as at 12. It 1s also provided with a central perforation and surrounding laterally deiiected wall 13,

which enters the central perforation within theplate or disk 5, and the latter circumferent1al ange 11 telescopically engages the metal rim 6 that surrounds the outer p riphery of the disk 5. The disk 5 is Ke assoclation with the housing 10 by the frictional engagement of the4 rim 6 with the flange 11, or by any other suitablemeans that may be provided for the purpose'.

`Passlng through one-of the perforations 12, in the ange 11 is an insulatingbutton 14,through which current conducting wires 15 and-16 pass into the interior of the housing 10. The wiresa-re connected to the termlnals 8 and 9, respectively, of the disk 5, but intermediate the terminal 8 and the wire 15 ,is an automatic heat responsive thermostat 17 secured to the bottom of the housing 10, as by nuts 18 and screws that pass through the bottom wall of the housing. A plate 19 forms the base of the thermostat and at each end a piece 20 and 21, respectively, is turned up for attachment of parts eldiin ufoA of thethermostat. The thermostatic bar 22 is insulatedly connected to the upturned part- 21, by screws 23, and an adjustable contact screw 24, adapted for association with the contact 25 carried by the thermostatic bar, is insulatedly secured 1n the upturned portion 20. The screw is accessible for adjustment through a perforation 12, made in the wall ing conductor is closed, and when the heat from the conductor 7 embedded in the disk 5 has reached a predetermined degree its ef- -fect upon the thermostatic bar 22, will be to curve it ina direction to carry the contact V25 away from the lcontact screwv 24 and thereby to open the circuit. The circuit will remain open until the disk 5 cools to some extent when the bar will be restored to its normal circuit closing position, as common with thermostatic bars of this character. It is the heat that radiates from the disk vwhich directly controls the action of the thermostatic bar 22 rather than the current that passes through the bar for the purpose of heating the resisting conductor, although' they conjointly coperate upon the bar.

The glass plate, or slide 26, upon which the subject to be examined is mounted is placed over the perforation in the center of the device so that the light reflected by the mirror 27 may pass through the perforation and illuminate thembject upn the slide 26. Considerable surface of the plate 26 rests upon the fiat surface of the disk 5, and in `that way heat is communicated to the object plate, and the aperture 26 within the device contains air that has been heated,

as the result of the effect of the electric current upon the electrostatic conductor.

VA. thermometer 28 ismounted upon the upper surface of the disk 5 Within easy View of the observer. -This thermometer will indicate -`.substantially the same temperature as that to which the plate 26 has been heated. In order that it ma7 be affec'ted as little by extraneous infiuences as .may b e, I place a cork covering 29 over the bulb of the thermometer and hold it in place by a cap 30, secured to the base 3l of the thermometer, by means of the pin or screw. 32.

On the bottom of the housing 10 is a soft rubber disk 33 secured thereto as by cement or otherwise, lthe object of which is to prevent the warm stage from slipping off of the microscope stage 34 when the latteris inclined to a greater or less extent. The friction engendered by the surface of the rubber tends to hold the warm stage in its position on the fixed stage ofthe microscope.

While I'have herein shown a single embodiment of my invention for the purpose of clear disclosure, it is evident that considerable changes may be made in the specic form and arrangement of parts Within the scope of the appended claims.

Having described my invention, .what I claim 1s l. A warm -stage for a microscope comprising a centralliT perforated plate; an electric conductor encompassing said perforation to heat the plate; a metal housing 2. In a structure of the character described the combination of a support comprising a central tube, a base part radiating from the 'lower end` of the tube, the outer edge portion of the base part being upturned to form a peripheral wall; andan electric heating disk adapted to fit within the peripheral wall and having `a central opening therethrough to receive said tube.

3. In a structure of the character described the combination of a support comprising a central tube, a base part radiating yfrom the lower end of the tube, the outer edge portion of the base part being upturned to form a peripheral wall; and an electric heating disk positioned with its outer edge within said peripheral Wall and its lower face spaced'away from the base part to provide an air chamber therebe- -tween, said disk having a central perforation to receivethe said tube.

4. In a structure of the character `de scribed the ycombination of a support comprising a central tube, a base part radiating from the lower end of the tube, the outer edge portion of the base part being upturned to form a peripheral wall; an electric heating disk positioned with its outer edge within said peripheral wall and its lower face spaced away from the base part to provide an air chamber therebetween, said disk having a central perforation to receive the said tube and a current varyingl thermo-responsive element positioned within said air chamber.

In testimony whereof I` hereunto set my hand in the presence of two subscribing wit` nesses.

TIODOLF LIDBERG.

In the presence of .STANLEY W. Coon, MARY F. ALLEN. 

